U.S. patent number 7,477,518 [Application Number 12/033,327] was granted by the patent office on 2009-01-13 for sub-assembly.
This patent grant is currently assigned to Infineon Technologies AG. Invention is credited to Richard Boettcher, Thilo Stolze.
United States Patent |
7,477,518 |
Stolze , et al. |
January 13, 2009 |
Sub-assembly
Abstract
According to an embodiment, a power semiconductor module
comprises a heat-dissipation contact area configured to thermally
connect the power semiconductor module to a cooling element. The
power semiconductor module also comprises a housing and a press-on
element. The press-on element comprises an anchoring region and is
captively anchored in the housing. A fixing eye is resiliently
coupled with the anchoring region.
Inventors: |
Stolze; Thilo (Arnsberg,
DE), Boettcher; Richard (Warstein, DE) |
Assignee: |
Infineon Technologies AG
(Neubiberg, DE)
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Family
ID: |
39583597 |
Appl.
No.: |
12/033,327 |
Filed: |
February 19, 2008 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20080158822 A1 |
Jul 3, 2008 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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11682483 |
Mar 6, 2007 |
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PCT/EP2005/007514 |
Jul 12, 2005 |
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Foreign Application Priority Data
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Sep 6, 2004 [DE] |
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10 2004 043 019 |
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Current U.S.
Class: |
361/715; 165/185;
257/712; 257/719; 257/E23.084; 257/E25.016; 361/704; 361/717 |
Current CPC
Class: |
H01L
23/049 (20130101); H01L 23/32 (20130101); H01L
23/4006 (20130101); H01L 25/072 (20130101); H01L
2023/405 (20130101); H01L 2023/4081 (20130101); H01L
2224/48091 (20130101); H01L 2224/48091 (20130101); H01L
2924/00014 (20130101); H01L 24/48 (20130101); H01L
2924/00014 (20130101); H01L 2924/00014 (20130101); H01L
2224/45099 (20130101); H01L 2924/00014 (20130101); H01L
2224/45015 (20130101); H01L 2924/207 (20130101); H01L
2924/181 (20130101); H01L 2924/181 (20130101); H01L
2924/00 (20130101) |
Current International
Class: |
H05K
7/20 (20060101); H01L 23/24 (20060101) |
Field of
Search: |
;361/704,707,709-710,714-715,717-719,760,772-773,776
;165/104.33,185 ;257/688,696,706-707,712-713,718-719 ;174/16.3 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
FS50R06W1W3 Datasheet, Daniel Kreuzer, May 11, 2007, Revision 2.0.
cited by other .
FS30R06W1E3 Datasheet, Daniel Kreuzer, Jun. 29, 2007, Revision 2.0.
cited by other .
FS20R06W1E3 Datasheet, Daniel Kreuzer, Jun. 29, 2007, Revision 2.0.
cited by other.
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Primary Examiner: Gandhi; Jayprakash N
Assistant Examiner: Hoffberg; Robert J
Attorney, Agent or Firm: Coats & Bennett, P.L.L.C.
Parent Case Text
CROSS-REFERENCE TO RELATED APPLICATION
This application is a continuation-in-part of co-pending U.S.
patent application Ser. No. 11/682,483 filed Mar. 6, 2007, which is
a continuation of International Application No. PCT/EP2005/007514
filed Jul. 12, 2005 designating the United States, which claims
priority to German application number DE 10 2004 043 019.5 filed
Sep. 6, 2004.
Claims
What is claimed is:
1. A power semiconductor module, comprising: a heat-dissipation
contact area configured to thermally connect the power
semiconductor module to a cooling element; a housing; a press-on
element comprising an anchoring region captively anchored in the
housing; a fixing eye resiliently coupled with the anchoring
region, the fixing eye having a mounted position different from an
un-mounted position; and wherein the press-on element is configured
to press the power semiconductor module against the cooling element
when the fixing eye is pressed against the cooling element in the
mounted position.
2. The power semiconductor module as claimed in claim 1, wherein
the press-on element comprises a spring arm joining the fixing eye
with the anchoring region.
3. The power semiconductor module as claimed in claim 2, wherein
the spring arm is partly separated from the fixing eye by a
cut.
4. The power semiconductor module as claimed in claim 3, wherein
the spring arm is joined with the fixing eye by a web.
5. The power semiconductor module as claimed in claim 4, wherein
the press-on element comprises a bent over end arranged adjacent to
the web opposite the cut.
6. The power semiconductor module as claimed in claim 5, wherein
the bent over end is bent upwardly away from a plane of the
heat-dissipation contact area.
7. The power semiconductor module as claimed in claim 1, wherein:
the housing comprises a mold compound; and the anchoring region
comprises at least one opening embedded in the mold compound.
8. The power semiconductor module as claimed in claim 1, wherein
the press-on element, in an un-mounted state, is spaced distant
from a plane of the heat-dissipation contact area.
9. A power semiconductor module, comprising: a heat-dissipation
contact area configured to thermally connect the power
semiconductor module to a cooling element; a housing comprising a
mold compound; a press-on element having an anchoring region
captively anchored in the housing; at least one opening formed in
the anchoring region and embedded in the mold compound; a fixing
eye resiliently coupled with the anchoring region, the fixing eye
having a mounted position different from an un-mounted position;
and wherein the press-on element is configured to press the power
semiconductor module against the cooling element when the fixing
eye is pressed against the cooling element in the mounted
position.
10. The power semiconductor module as claimed in claim 9, wherein
the press-on element comprises a fixing eye resiliently coupled
with the anchoring region.
11. The power semiconductor module as claimed in claim 10, wherein
the press-on element comprises a spring arm joining the fixing eye
with the anchoring region.
12. The power semiconductor module as claimed in claim 11, wherein
the spring arm is partly separated from the fixing eye by a
cut.
13. The power semiconductor module as claimed in claim 12, wherein
the spring arm is joined with the fixing eye by a web.
14. The power semiconductor module as claimed in claim 13, wherein
the press-on element comprises a bent over end arranged adjacent to
the web opposite the cut.
15. The power semiconductor module as claimed in claim 14, wherein
the bent over end is bent upwardly away from a plane of the
heat-dissipation contact area.
16. The power semiconductor module as claimed in claim 9, wherein
the press-on element, in an un-mounted state, is spaced distant
from a plane of the heat-dissipation contact area.
Description
BACKGROUND OF THE INVENTION
The invention relates to a power semiconductor module comprising a
heat-dissipation contact area for thermally conductive connection
to a cooling element.
A module construction of this type is customary and known e.g. from
DE 199 42 915 A1. Said known module comprises an insulating and
thermally conductive carrier (substrate) composed e.g. of a ceramic
material coated e.g. with copper (DCB) on both sides. Conductor
track structures are formed in the top side coating, a plurality of
power semiconductors being electrically connected to the
structures. The substrate underside functions as a heat-dissipation
contact area in order to be able to dissipate power losses
occurring in the form of heat during operation to a heat sink. For
this purpose, a press-on device engaging over a plurality of
substrates is provided, having pressure pieces which both serve for
electrical contact-connection and press the substrates onto the
heat sink.
DE 297 20 480 U1 and DE 200 14 739 U1 show press-on elements in the
form of a clip which is connected by at least one fixing region to
the cooling element in a positively locking manner (DE 297 20 480
U1) or by screw connection (DE 200 14 739 U1). A press-on region of
the clip presses the component to be cooled onto the cooling
element by its heat-dissipation contact area.
The mounting of the known power semiconductor module on the cooling
element is complicated and cost-intensive because the press-on
element/elements has/have to be handled, supplied and mounted
separately in the mounting process. Depending on the configuration
of the power semiconductor module and the press-on element,
mounting errors may occur in this case--e.g. as a result of
defective positioning or orientation--and said mounting errors
influence the cooling effect and hence the operational reliability.
Moreover, the connection between power semiconductor module and
press-on element involves dimensional tolerances which have an
unforeseeable effect on the magnitude of the press-on forces
exerted.
SUMMARY OF THE INVENTION
According to an embodiment, a power semiconductor module comprises
a heat-dissipation contact area configured to thermally connect the
power semiconductor module to a cooling element. The power
semiconductor module also comprises a housing and a press-on
element. The press-on element comprises an anchoring region and is
captively anchored in the housing. A fixing eye is resiliently
coupled with the anchoring region.
Of course, the present invention is not limited to the above
features and advantages. Those skilled in the art will recognize
additional features and advantages upon reading the following
detailed description, and upon viewing the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of an embodiment of a power semiconductor
module in longitudinal section.
FIG. 2 is a diagram of the power semiconductor module of FIG. 1 in
plan view.
FIG. 3 is a diagram of another embodiment of a power semiconductor
module in plan view.
FIG. 4 is a diagram of the power semiconductor module of FIG. 3 in
side view.
FIG. 5 is a diagram of an embodiment of the press-on elements of
the module of FIGS. 3 and 4 in perspective view.
FIG. 6 is a diagram of the module of FIGS. 3 and 4 mounted on a
cooling element.
DETAILED DESCRIPTION OF THE INVENTION
A power semiconductor module is thermally connected to a cooling
element in a simple, cost-effective and reliable manner. According
to an embodiment, the power semiconductor module comprises at least
one press-on element which is captively connected to the power
semiconductor module. The press-on element presses a
heat-dissipation contact area of the module onto the cooling
element in the mounted state, thereby ensuring a desired reliable
thermally conductive contact between the power semiconductor module
and cooling element.
In an embodiment, the press-on element, upon connection of a module
to a cooling element, does not have to be separately delivered,
stored, handled, supplied and finally mounted at the power
semiconductor module. Since the press-on element is configured as
an integral element that is captively connected to the power
semiconductor module, it advantageously forms an (in this respect
prefabricated) sub-assembly for simple and cost-effective mounting
on and connection to the cooling element. Since the connection
between the power semiconductor module and the press-on element is
prefabricated (in an automated manner), significantly smaller
tolerances can also be complied with, thereby reducing the power
semiconductor module/press-on element/cooling element tolerance
chain that determines the press-on forces.
A further advantage, according to an embodiment, consists in the
fact that suitably dimensioned press-on elements can be fixedly
assigned and predetermined by the manufacturer. During mounting,
therefore, the user is not faced with the task of having to
dimension or assign suitable press-on elements. Various power
semiconductor modules (e.g. with different powers) can thus be
provided with uniform press-on elements, which further simplifies
stock keeping and logistics.
According to one embodiment, the power semiconductor module
comprises a press-on element having an anchoring region and a
fixing eye. The anchoring region is captively anchored in a housing
of the module. The fixing eye is resiliently coupled with the
anchoring region.
In another embodiment, the power semiconductor module comprises a
housing which is formed from a mold compound, and a press-on
element. The press-on element comprises an anchoring region with at
least one opening, which is embedded in the mould compound. Such
configuration can be achieved by injection-molding the anchoring
region with its at least one opening into the material of an
injection-molding housing of the power semiconductor module.
FIG. 1 shows a power semiconductor module comprising a substrate 1,
which is embodied as a ceramic lamina coated with copper (DCB) on
both sides. On the top side 2, in a manner known per se, a
plurality of power semiconductors 3, 4 are arranged and connected
by base-side soldering and/or bonding wires 5, 6 to conductor
tracks 7 formed on the top side. In addition, electrical connection
contacts, e.g. 9, 10, extend upward. The substrate 1 and the power
semiconductor arrangement are covered by a plastic housing 12
produced by injection molding. The underside 14 of the substrate
simultaneously forms the lower outer area and serves by virtue of
its copper coating--formed over the whole area--as heat-dissipation
contact area 16 for thermally conductive connection to a cooling
element 17.
Press-on elements 18, 19 shaped in clamp-type fashion with a
respective anchoring region 20, 21 are in each case
injection-molded into the housing 12 on both sides. The housing
material (plastic) thus surrounds the anchoring regions and
provides for a fixed, captive seating of the press-on elements. The
press-on elements thus already become integral constituent parts of
the power semiconductor module in a very early manufacturing
stage--preferably during the production of the housing 12. For this
purpose, the press-on elements can be inserted as insert parts into
the plastic injection-molding mold for the housing and be
integrated in a single injection-molding operation--which is
required anyway for producing the housing 12.
FIG. 2 shows the arrangement and configuration of the press-on
elements 18, 19 in plan view for illustration. A symmetrical
arrangement of the press-on elements 18, 19 is chosen here; this is
not mandatory, however. Asymmetrical configurations or
else--depending on the press-on force desired--only one press-on
element or more than two press-on elements are likewise
conceivable. The press-on elements 18, 19 have holes 23, 24 through
which fixing screws 25, 26 (FIG. 1) can reach for the releasable
mounting of the module on the cooling element 17.
As indicated by arrows (FIG. 1), the press-on elements 18, 19 are
pressed onto the top side 29 of the cooling element 17 by the
screws 25, 26 reaching into threaded holes 27, 28, respectively. In
this case, the press-on elements 18, 19 generate the desired
homogeneous press-on forces on account of their spring-elastic
properties. The power semiconductor module therefore combines the
advantages of the press-on properties that can be generated by
press-on elements or resilient clamps with a simple and
cost-effective realization of the connection to the cooling element
17.
FIG. 3 shows a plan view of another embodiment of a power
semiconductor module. This module may have the same interior
configuration as the module described in FIG. 1. The module of FIG.
3 also comprises a plastic housing 12 produced by injection
molding, connection contacts 9, 10 for electrically connecting the
module, and press-on elements 18, 19 shaped in clamp-type fashion.
Each of the press-on elements 18, 19 comprises a respective
anchoring region 20, 21 (plotted in dashed lines) which is
injection-molded into the housing 12.
Further, the press-on elements 18, 19 comprise fixing eyes 35, 36,
spring arms 41, 42, 43, 44, and bent over ends 31, 32, 33, 34,
respectively. In each of the fixing eyes 35, 36, a hole 23 and 24,
respectively, is formed through which fixing screws (not shown) can
reach for the releasable mounting of the module on a cooling
element 17. The press-on elements 18, 19 comprise spring arms 42,
43 and 41, 44, respectively, joining the anchoring regions 20, 21
with the respective fixing eye 35 and 36, and with the respective
bent over ends 31, 33 and 32, 34 so as to resiliently couple the
fixing eyes 35, 36 with the respective anchoring region 20, 21,
i.e. with the plastic housing 12.
The spring arms 41, 42, 43, 44 are partly separated from the
respective fixing eyes 35, 36 by cuts 51, 52, 53, 54 which are
formed in the press-on elements 18, 19 such that between each of
the spring arms 41, 42, 43, 44 and the respective fixing eye 35, 36
a connection web 61, 62, 63 and 64, respectively, remains. To
protect these webs 61, 62, 63, 64 from kinking when mounting the
module on the cooling element 17, the press-on elements 18, 19
comprise bent over ends 31, 32, 33, 34 which are arranged adjacent
to the respective webs 61, 62, 63, 64 opposite the respective cut
51, 52, 53, 54.
FIG. 4 shows the un-mounted module of FIG. 3 in side view. In the
un-mounted state, the spring arms 41, 42, 43, 44 are relaxed and
the press-on elements 18, 19 are spaced distant from the plane of
the underside 14. As can be seen from FIG. 4, the ends 31, 32, 33,
34 of the press-on elements 18, 19 are bent upwardly.
As already described above, the anchoring regions 20, 21 of the
press-on elements 18, 19 are injection-molded into the housing 12
such that the anchoring regions 20, 21 are surrounded by the
plastic material of the housing 12. To facilitate unhinging of the
housing 12 from the mold after the injection-molding process, the
molding compound may comprise a mold release agent. However, such
mold release agent also affects the fixing of the anchoring regions
20, 21 in the housing 12. In order to improve this fixing, the
anchoring regions 20, 21 may comprise at least one, or as shown in
the press-on element 18, 19 in FIG. 5, a number of openings 50
through which the mold compound can penetrate during the
injection-molding process, which results in an improved fixing.
FIG. 6 shows the module of FIGS. 3 and 4 when being mounted on a
cooling element 17 by use of fixing screws 25, 26. In the mounted
state, the fixing eyes 35, 36 are pressed against the cooling
device 17 due to the down forces generated by the fixing screws 25,
26. Thereby, tension will be generated in the webs 61, 62, 63, 64
which press the module resiliently against the cooling device
17.
With the above range of variations and applications in mind, it
should be understood that the present invention is not limited by
the foregoing description, nor is it limited by the accompanying
drawings. Instead, the present invention is limited only by the
following claims and their legal equivalents.
* * * * *